1. Field of the Invention
This invention relates to methods and devices that are used in implant dentistry to replace a natural tooth with a prosthetic tooth. More particularly, the invention relates to an improved healing cap that covers a dental implant after stage one surgery and an insertion tool that can be used to insert and/or remove the healing cap.
2. Description of the Related Art
Implant dentistry involves the restoration of edentulous area(s) in a patient""s mouth using artificial components, including typically an implant fixture or root and a prosthetic tooth and/or final abutment which is secured to the implant fixture. According to state of the art techniques, the process for restoring a tooth and its root is carried out generally in three stages.
Stage I involves implanting the dental implant fixture into the bone of a patient""s jaw. The oral surgeon first accesses the patient""s jawbone through the patient""s gum tissue and removes any remains of the tooth to be replaced. Next, the specific site in the patient""s jaw where the implant will be anchored is widened by drilling and/or reaming to accommodate the width of the dental implant fixture to be implanted. Then, the dental implant fixture is inserted into the hole in the jawbone, typically by screwing, although other techniques are known for introducing the implant in the jawbone.
The implant fixture itself is typically fabricated from commercially pure titanium or a titanium alloy. Such materials are known to produce osseointegration of the fixture with the patient""s jawbone. The dental implant fixture also typically includes a hollow threaded bore through at least a portion of its body and extending out through its proximal end which is exposed through the crestal bone for receiving and supporting the final tooth prosthesis and/or various intermediate components or attachments.
After the implant is initially installed in the jawbone a temporary healing screw or healing cap, which is ordinarily made of a dental grade metal, is secured over the exposed proximal end in order to seal the internal bore. The healing screw typically includes a threaded end, which is screwed into the internal bore of the implant. After the healing screw is in place, the surgeon sutures the gum over the implant to allow the implant site to heal and to allow desired osseointegration to occur. Complete osseointegration typically takes anywhere from four to ten months.
During stage II, the surgeon re-accesses the implant fixture by making an incision through the patient""s gum tissues. The healing screw is then removed, exposing the proximal end of the implant. A mold or impression is then taken of the patient""s mouth to accurately record the position and orientation of the implant within the mouth. This is used to create a plaster model or analogue of the mouth and/or the implant site and provides the information needed to fabricate the prosthetic replacement tooth and any required intermediate prosthetic components. Stage II is typically completed by attaching to the implant a temporary healing abutment or other transmucosal component to control the healing and growth of the patient""s gum tissue around the implant site.
Stage III involves fabrication and placement of a cosmetic tooth prosthesis to the implant fixture. The plaster analogue provides laboratory technicians with a model of the patient""s mouth, including the orientation of the implant fixture relative to the surrounding teeth. Based on this model, the technician constructs a final restoration. The final step in the restorative process is replacing the temporary healing abutment with the final restoration.
There are several recurring problems or difficulties associated with securing the healing screw or cap to the implant during stage one and with removing the healing screw or cap during stage two surgery. For example, screwing the healing screw into the implant during stage one is time consuming, difficult and requires a secondary tool such as a screwdriver. Moreover, because the healing screw is small, it is difficult to handle and may be accidentally dropped into the patient""s mouth if adequate care is not taken. Unscrewing the healing screw from the implant during stage two also is time consuming, difficult and requires an additional tool such as a screwdriver. Furthermore, the healing screw also may be accidentally dropped into the patient""s mouth as it is removed from the implant if adequate care is not taken.
It should be appreciated that a set of two or more teeth can be replaced using the same procedure outlined above. In such a case, a single implant supports two or more prosthetic teeth. The present invention applies equally to the replacement of one tooth or multiple teeth.
It is an objective of this invention to provide an improved dental implant and healing cap that enables a surgeon to quickly and simply attach the healing cap to the dental implant without the need for an additional tool. It is another object of this invention to provide a healing cap that is quickly and simply removed from the implant. It is yet another object of the invention to provide a healing cap made of an inexpensive injection-molded plastic or any of a variety of bio-compatible materials, such as, for example, titanium, stainless steel, ceramic, or any combination thereof.
In one embodiment, the present invention provides a combination comprising a dental implant, a healing cap for covering a top surface of the implant and a tool for inserting the healing cap. The dental implant has a coronal opening. The healing cap comprises a proximal end and a distal end. The proximal end is configured with one or more prongs adapted to be inserted into the coronal opening of the implant and to engage and secure the healing cap to the implant. The one or more prongs of the proximal end are adapted such that a healing cap removal force is required to disengage the healing cap from the dental implant. The distal end of the healing cap includes an indentation having a neck with a diameter smaller than a diameter of an adjacent portion of the indentation. The insertion tool comprises a first portion with one or more prongs adapted to be inserted into the indentation. The first portion is adapted such that a first removal force is required to remove the one or more prongs of the first portion from the indentation. The first removal force is less than the healing cap removal force.
In another embodiment, the present invention provides a set of dental components comprising a dental implant, a healing cap for covering a top surface of the dental implant when installed in a patient""s jawbone and an insertion tool. The healing cap comprises a first end adapted to be snappingly mated to the implant with a healing cap removal force. The healing cap also includes a second end adapted to completely cover the top surface of the implant. The insertion tool includes a first portion to be snappingly mated to the second end of the healing cap with a first removal force. The first removal force is less than the healing cap removal force.
In yet another embodiment, the present invention provides a method of installing and removing a healing cap that covers a top surface of an implant installed in a patient""s jawbone. The method comprises, in sequence, engaging in a snap fit a first portion of an insertion tool with a top portion of the healing cap, positioning the healing cap over a dental implant, inserting a proximal end of the healing cap into a coronal opening of the implant until the proximal end engages the coronal opening in a snap fit so as to secure the healing cap to the implant, and separating the first portion of the insertion tool from the top portion of the healing cap.
For purposes of summarizing the invention and the advantages achieved over the prior art, certain objects and advantages of the invention have been described herein above. Of course, it is to be understood that not necessarily all such objects or advantages may be achieved in accordance with any particular embodiment of the invention. Thus, for example, those skilled in the art will recognize that the invention may be embodied or carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other objects or advantages as may be taught or suggested herein.
All of these embodiments and obvious variations thereof are intended to be within the scope of the invention herein disclosed. These and other embodiments of the present invention will become readily apparent to those skilled in the art from the following detailed description of the preferred embodiments having reference to the attached figures, the invention not being limited to any particular preferred embodiment(s) disclosed.